1. Field of the Invention
The present invention relates to agricultural implements such as a planting apparatus for seeding, and fertilizing.
2. Description of the Prior Art
Various convertible type drills have been advanced in the past, generally using tool bar constructions with individual disc or furrow openers for providing a seed opening. For example, U.S. Pat. No. 4,311,104 shows a press grain drill that has a tool bar supporting a plurality of furrow openers, wherein the tool bar is attached to a lifting mechanism on the main frame, and is used for supporting the individual furrow openers separately. However, this device has a draft control mechanism for each individual furrow opener, and does not disclose true modular connections.
U.S. Pat. No. 4,377,979 illustrates a row crop planting system having a number of individual components such as tool bars joined together, and supported for movement over the ground. It includes forward tillage units and trailing seeding units, each of which is connected to a frame through four bar linkages.
U.S. Pat. No. 3,224,347 shows a multiple purpose tillage or soil processing machine having several individual sections for working the soil, and Pat. No. 2,657,652 illustrates a typical implement-seeder combination using chisel type furrow openers.
A soil tilling machine which includes a fertilizer spreader or seeder attachment at the rear is shown in U.S. Pat. No. 2,788,725. U.S. Pat. No. 2,951,458 illustrates a seeder box mounting and drive connection for use on cultivators.
Additionally, the present applicant's assignee has used modular drill boxes on a frame which has a removable tool bar carrying individual seeding units. The seeder assembly is mounted on a tool bar much like in U.S. Pat. No. 4,311,104, but only through a limited number of pivot connections so that it can easily be removed and replaced.
Further, individually depth controlled furrow openers using disc type openers in combination with pivoting frames are well known in the art.
Such a device is shown in U.S. Pat. No. 4,116,140, which is owned by the same assignee as this present application.
These devices show the common usage of pivoting shafts operated with hydraulic cylinders for raising and lowering tool bars, as also shown in U.S. Pat. No. 4,077,478. Thus using a tool bar that is raisable and lowerable relative to a frame through the use of hydraulic cylinders rotating a rock shaft is well known is shown only schematically in the present application. Also, individual depth control for the individual seeding mechanisms, and similar details are well known in the art and form no part of this present invention.